1. Technical Field
The present invention relates to a linear vibrator.
2. Description of the Related Art
The most important feature of an electronic device, such as a mobile phone, is the generation of vibration. A vibration motor is a means for generating vibration and is constructed so that its axis is eccentric or the center of gravity is non-uniformly distributed to one side and thereby the motor generates vibrations as it rotates.
However, the vibration motor is problematic in that a brush passes through a gap between segments when the motor rotates, so that friction and sparks are generated, and thus the lifespan of the motor is reduced. In addition to the problem, the vibration motor has other problems as well.
In order to overcome the drawbacks of the vibration motor, a linear vibrator has been developed. In the linear vibrator, a vibratory unit mounted to a spring vibrates while performing rectilinear motion in a vertical or horizontal direction as a result of an electromagnetic force between a magnet and a coil, so that friction and abrasion do not occur unlike in the vibration motor, and thus the lifespan of the linear vibrator is long. Further, the miniaturization of the linear vibrator is possible. Accordingly, a variety of types of linear vibrators are currently in development.
The conventional linear vibrator is constructed so that mechanical vibrations are generated by rotating a rotor having an eccentric mass body, and a rotating force is commutated through a contact point between the brush and a commutator, thus supplying electric current to the coil of the rotor.
However, the conventional linear vibrator is problematic in that mechanical friction and abrasion and electric sparks are generated while the brush is passing through a gap between a segment of the commutator and another segment, so that impurities such as black powder are generated, and thus the lifespan of the linear vibrator is short.
Therefore, research into a linear vibrator which can generate more stable linear vibration and stop vibrating rapidly and stably is urgent.